AHLSTROM; FISH LARVAE IN EASTERN TROPICAL PACIFIC 



130* 120° MO^ 



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Figure 8. — Distribution of larvae of the myctophid, Ceratoscopelus townsendi-complex on EASTROPAC I. 

 Collections of 1 to 25 larvae are shown as circles with dot in center, collections of 26 or more larvae as large 

 solid circles; negative hauls are shown as small solid circles. 



The genus Diaphics is not a natural assem- 

 blage, inasmuch as there are two distinctive 

 larval morphs for the species in the EASTRO- 

 PAC area. One group has slender-bodied larvae 

 with persistent ventral midline pigment on the 

 tail; the adults of this group possess both Vn 

 and So occular photophores (subgenus Diaphus 

 of Fraser-Brunner, 1949) . The other and larger 

 group has stubby-bodied larvae which usually 

 are but lightly pigmented; in the EASTROPAC 

 area the larvae of Diaphus pacificus Parr is a 

 representative example. 



Although Diaphus larvae were distributed 



over most of the area covered on EASTROPAC 

 I, they were least common in the inner pattern 

 occupied by Alaminos (21 occurrences, 71 lar- 

 vae) and most consistently taken in the inter- 

 mediate pattern occupied by Jordan (96 oc- 

 currences, 1,363 larvae) . 



Diogenichthys laternatus (Garman) (339 

 occurrences, 25,325 larvae) 



Although this is by far the most abundant 

 kind of larva taken on EASTROPAC I, it did 

 not occur in the central water mass of the South 



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